Packet switched digital networks are the backbone of the Internet. In a packet switched Internet Protocol (IP) network, digital information flowing from a source to a destination is broken up into a sequence of packets. These packets are routed through the network through a myriad of routers and switches. There is no guarantee that packets will all follow the same route. Routing, and route management, controls the routes packets follow, and how those routes change, adapt, and respond to network conditions such as loading and failures.
Packet traffic is switched between routers. A router is a computer networking device combining hardware and software to forward data packets toward their destination. A router connects to other routers, which, when using Border Gateway Protocol (BGP), are known as peers. This initial peering is generally established by manual configuration. Each router maintains a table of networks or prefixes which designate network reachability. Peered routers manage these tables by exchanging messages according to the Border Gateway Protocol (BGP), specified in RFC 1771.
Route Management is an area of active research in the Internet community as well as an area of interest to Network Service Providers (NSPs). By monitoring and managing routing, one can track problems missed by traditional network element and service monitoring and at the same time, gather information useful when evaluating peering. In order to conduct meaningful routing management as it pertains to Boarder Gateway Routing (BGP) protocol, it is necessary to collect individual routing updates from peer routers.
Software tools to record routing information are available from at least two sources. The first is Zebra or Quagga, which is a fully functional routing protocol suite, which happens to have the capability to record routing updates. Mrtd, part of the MRT package from the University of Michigan is also capable of recording routing updates. Both of these tools have their problems when used as a network instrument. First, they are built to do much more than is necessary to simply record routes. Both tools are capable of full BGP routing functionality and primarily because of this added processing, do not scale well. Second, the behavior of these tools interferes with the measurements they are trying to record. Both of the above mentioned tools will tear down the BGP peering session when they receive any error from the peer, in conformance to the BGP specification.